The present invention relates to a pump device for supplying fuel from a tank to an internal combustion engine, and comprising a high-pressure pump and a low-pressure pump, the second connected upstream from the first.
A pump device of the aforementioned type is described, for example, in DE 41 26 640 A1, and forms part of an injection system which, in addition to the high- and low-pressure pumps, also comprises numerous electromagnetic injectors and other hydraulic components. The low-pressure pump is normally a rotary-vane or -roller pump which is operated by a small electric motor and housed directly inside the tank. Despite the high technical standard of modern internal combustion engine injection system components, defects involving, for example, the low-pressure pump or injectors cannot be altogether avoided and result in irregular fuel supply and, in extreme cases, in irreparable damage to the engine.